<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <!--
        主轴默认横向排列
        侧轴默认竖向排列
    -->
    <style>
        .box{
            width: 500px;
            height: 500px;
            border: 2px solid black;
            margin: 100px auto;
            display: flex;
            /* 弹性盒 */
            /* flex-direction: column; */
            /* flex-direction: row; */
            /* flex-direction: row-reverse; */
            flex-direction: column-reverse;
            /* 
            colun    列
            flex-direction: column;     竖向排列
            flex-direction: row;        水平排列
            flex-direction: row-reverse;    水平反向排列
            flex-direction: column-reverse; 垂直反向排列                   
            */
        }
        .box span{
            width: 100px;
            height: 100px;
            border: 1px dashed red;
        } 
    </style>
</head>
<body>
    <div class="box">
        <span>1111</span>
        <span>2222</span>
        <span>3333</span>
        <span>4444</span>
    </div>
</body>
</html>